One of Week 3's most highly anticipated games featuring two of the best young quarterbacks in the NFL in the Colts' Andrew Luck and his counterpart, Colin Kaepernick, was defined by defense. Both precocious signal-callers struggled to a degree, but Luck was clearly the better one on the day.

The Niners are usually the team that takes it to opponents with physicality and a will-crushing running game, but it was Indianapolis that controlled the clock with a ground-and-pound attack.

That mind-set was established early, when recently acquired running back Trent Richardson plunged in for a one-yard touchdown to help put the Colts up 7-0 early.

The seven-play, 80-yard drive came after San Francisco went three-and-out to open the game. That was something that became commonplace for Kaepernick and Co., as it happened four times in the game.

San Francisco responded in the opening quarter with an impressive 90-yard scoring drive, though, capped off by running back Kendall Hunter's 13-yard run after Frank Gore was the workhorse in leading the offense down the field.

From there, it seemed the Niners had a chance to seize the momentum, but Chuck Pagano's Colts held their ground—particularly in the secondary.

Indy D is playing press coverage on the 49ers' WRs and just not a lot of room, not much for Kaepernick to throw to.

Anquan Boldin had five catches for 67 yards, but no one else in his WR corps managed a reception on the afternoon until Kyle Williams' garbage-time catches in the closing minutes.

Ahmad Bradshaw spearheaded the Colts' ground game by running for a game-high 95 yards, with 62 of them coming after halftime.

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That pounding against a fatigued San Francisco defense led to the icing touchdown by Luck, who faked a handoff and took a bootleg inside the pylon for a six-yard score to make it 20-7 at the 4:13 mark of the fourth quarter.

The Colts were able to impose their will and capitalized on a groin injury to superstar linebacker Patrick Willis near the end of the third quarter, where the team's official Twitter reported he wouldn't return:

Without Willis in the heart of the defense, it simply wasn't the same.

A strip-sack of Kaepernick and a late touchdown by Bradshaw put to rest any hopes of a comeback for the home team.

It was an uncharacteristically sloppy performance for the Niners, who've suffered back-to-back losses for the first time under head coach Jim Harbaugh's tenure.

Grades

Andrew Luck, QB, Indianapolis Colts: A-

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It was a brutal matchup, but Luck did just enough in the passing game in completing 18 of 27 passes for 164 yards to allow running lanes to open up for Bradshaw, Richardson, Donald Brown and himself.

Offensive coordinator Pep Hamilton has wanted to implement more of a power rushing attack, and that was no more evident than on Sunday. Luck made smart decisions against his former college coach's team and continued to live up to the hype as Peyton Manning's worthy successor.

Colin Kaepernick, QB, San Francisco 49ers: D

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For the second consecutive contest, Kaepernick was a shell of his explosive self (13 of 27, 150 yards, 0 TD, 1 INT).

Before the final drive—which ended in a forced interception—he hadn't eclipsed the 100-yard mark through the air. Kaepernick also carried the ball just seven times for 20 yards and was too hesitant on the perimeter.

Although his receivers struggled to get separation and frequently gave Kaepernick nowhere to go, he wasn't decisive enough and finished with a passer rating of 49.9.

Jerrell Freeman, LB, Indianapolis Colts: A

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The tone-setters for the Colts defense were the aggressiveness of the secondary and the play of Freeman in the middle of the front seven.

Freeman finished with a team-high eight total tackles (seven solo), including a sack. That helped make up for the absence of safety LaRon Landry, who was ruled out with an ankle injury.

The former undrafted player out of Division III Mary-Hardin Baylor continues to emerge as one of the more underrated linebackers in the game, and his performance on Sunday fortified that notion.

Frank Gore, RB, San Francisco 49ers: A

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Which team is likelier to miss the playoffs?

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Which team is likelier to miss the playoffs?

San Francisco 49ers (1-2)

64.6%

Indianapolis Colts (2-1)

35.4%

Total votes: 3,589

Credit the bruising Gore for making the most of his 11 carries in racking up 82 yards, but the game plan didn't go through him often enough.

As dynamic of an athlete as Kaepernick is, offensive coordinator Greg Roman may want to call Gore's number more often.

Gore also caught two passes for 21 yards but has no longer been the vessel through which the Niners channel their hard-nosed style. That needs to change if the receiver-weak offense is meant to thrive this season.

What's Next?

This is a monumental win for the Colts away from home after a tough 24-20 loss to the Miami Dolphins in Week 2. Indianapolis opens the AFC South slate in 2013 with a trip to play the Jacksonville Jaguars, which should result in an easy win.

Meanwhile, the injury to Willis is definitely a concern for the 49ers, who are on a short week and have to play in Week 4's Thursday night (away) game against the NFC West rival St. Louis Rams.